Electricity

1
Electricity Magnetismat Work

• Using Electric Power
• Chapter 3
• Section 3

2
Electric Power

• The rate at which energy is converted from one
  form into another.

• James Watt
• 1700s
• Designed Steam Engines

3
Power Ratings

• Stove 6,000 W
• Clothes Dryer 5,400 W
• Water Heater 4,500 W
• Washing Machine 1,200 W
• Dishwasher 1,200 W
• Hair Dryer 1,200 W
• Iron 1,100 W
• Microwave 1,000 W
• Coffee maker 1,000 W

• Toaster 850 W
• Food Processor 500 W
• Fan 240 W
• TV 100 W
• Clock radio 12 W

4
Calculating Power

• Power Voltage x Current
• Watts Volts x Amps

5
Power Problem

• A household light bulb has approximately 0.5 amps
  of current flowing through it.
• Since the standard household voltage is 120 V,
  what is the power rating of the light bulb?

• P V x A

6
Paying for Energy

• Energy Power x Time

• Kilowatt-hour
• kWh
• 0.10 each

7
High Voltage Power

• 10,000 - 800,000 V
• More efficient for long distance conduction

• House Appliances
• Use 120 V

8
Transformers

• A devise that increases/decreases voltage

• Primary Wire induces a current onto a secondary
  wire
• Step Up Transformer
• Step Down Transformer

9
Hans Christian Oersted

• 1820
• Electromagnetism
• Discovers that an electric current creates a
  magnetic field

10
Michael Faraday Joseph Henry

• 1830
• Electric Induction
• Discover that an electric current can be induced
  by a changing magnetic field

11
Thomas Edison

• 1882
• Opens his first DC electric producing power plant
  in New York City.
• It provided 120 V to 2.6 square kilometers of
  customers.

12
Nikola Tesla

• 1888
• Received patents for distributing power via high
  voltage AC, using step up/down transformers

13
Nikola Tesla

• 1893
• AC is used to power the Worlds Fair in Chicago